1. Field
The described apparatus and method relates generally to high availability computers and, in particular, to methods for secure, unattended installation of operating systems for such machines. In particular, the current invention is directed to an unattended and secure installation of an operating system over a computer network.
2. Description of the Related Art
An operating system often is the most critical piece of software in a computer system as it is the software that controls the allocation and usage of hardware resources, such as memory, central processing unit time, disk space, and peripheral devices. Typically, an operating system provides a “platform” by exposing application programming interfaces (APIs) that applications use to call upon the operating system's underlying software routines to perform functions.
The most common operating systems are proprietary systems such as Microsoft Windows and Windows 2000 (formerly known as Windows NT), and systems based on open source such as Linux. Typically, an operating system executes on standard off-the-shelf hardware such as an Intel-based processor.
Operating system installation techniques are well known in the art. Representative patents include U.S. Pat. Nos. 6,128,734, 5,325,532, 5,758,165, 5,142,680, 5,280,627, and 5,452,454. The '734 patent, issued to Gross et al., is representative. There, a computer system is upgraded while the computer system is functioning. In particular, the computer system has a first boot device with a first operating system, and a second device. The second device is prepared within the computer system as a bootable device while the computer system is functioning under control of the first operating system. In particular, the second device is prepared to receive a second operating system. The second operating system is loaded onto the second device while the computer system is functioning under control of the first operating system. Thereafter, the computer system is rebooted. Upon reboot, the computer system is under control of the second operating system on the second device.
While the installation technique shown in the '734 is advantageous, remote operating system installation raises difficult challenges. In general, of course, any corruption of an operating system is problematic, but the matter is exacerbated when the machine is remotely located and/or otherwise not readily available by direct physical access. This situation may arise, for example, when the machine is located in a third party premise. Remote installation of an operating system may also involve the destruction of the pre-existing operating system. Of course, when a then-current operating system is corrupted, the options for remote repair or replacement are generally very limited in scope.
Further, even when the operating system kernel is not corrupted or damaged, the mere replacement of one operating system with another may cause instability of the platform. For example, if operating system A is completely replaced with operating system B while operating under operating system A (as described, for example, in the '734 patent) a new set of scripts, procedures, and/or executables may need to be implemented.
In this manner, many typical networked computing devices running operating systems and methods of remote installation of the same suffer one or more shortcomings. Many other problems and disadvantages of the prior art will become apparent to one skilled in the art after comparing such prior art with the present invention as described herein. Other aspects, advantages, and novel features of the present invention will become apparent from the detailed description of the invention when considered in conjunction with the adaptively clocked accompanying drawings.